An axial-flow gas turbine engine comprises a rotary assembly forming a compressor, feeding a fixed combustion chamber which itself delivers hot gases to a rotary assembly forming a turbine. A turbine rotor fixedly attached to a compressor rotor forms a body and the engine may comprise one or more bodies, usually two or three rotating at different speeds. Thus a double-bodied engine comprises a low pressure LP body and a high pressure HP body. In order to make it easier to mount the engine and reduce the mounting and removal times, its architecture is often divided into modules. For example, for the high pressure body of a double-bodied engine, all the parts forming the compressor are placed in an HP compressor module and all the parts forming the turbine rotor are placed in an HP turbine module.
The latter module consists only of the rotating parts, for example a turbine disk onto which a labyrinth seal assembly and a shell with an upstream assembly flange and a seal assembly associated with a downstream bearing are bolted.